how to evict a tenant in arrears and whom never responds

Rent Arrears

I have a tenant who has been living in the property for over the 1 year contract so it should just be rolling on a two month notice by now.
The tenant has been getting worse in paying and is now about 6 weeks in arrears. I want to evict him now (doubting i will see the lost rent anyway) - but he doesn't answer the phone, or text & when i go to the property he doesn't answer (he has a camera facing the doorway).
This is my first experience of having to evict a tenant, could you please advise me on how i should proceed ?
Although i obviously want to retrieve the lost rent, my main concern is to get him out of my property.
p.s. i didn't issue a 21 notice when i started the tenancy.
Regards
Russell